Fluid supply system



April 3, 1934. J. N. HARDY FLUID SUPPLY SYSTEM Filed Feb. 5, 1932 JOIHN N.H

Patented Apr. 3, 1934 UNHTED STATES ATE FECE

7 Claims.

My invention relates to fluid-supply systems, and especially to liquid supply systems such as an oil supply system for an oil burning furnace. More particularly, my invention relates to a valve for use in such a system.

In an oil supply system for the oil burner of a furnace, there is usually a storage tank for the oil, an oil pump, a supply line leading from the tank to the oil pump, and suitable connections through which the pump supplies oil under pressure to the burner. The pump is usually of a type through which oil can flow only when the pump is in operation, so that oil can not fiow from the tank into the furnace except when the pump is in operation. However, the pump often cuts off the fiow of oil into the furnace only imperfectly so that some oil is allowed to leak into the furnace where it may be ignited with considerable violence when the burner is ignited; or the oil may leak from the furnace into the room in which the furnace is situated. Also, leaks may occur in the oil supply line and permit a substantial quantity of oil to leak from the tank directly into the basement of a building, when the furnace is used for heating such a building. Such oil leaks produce a dangerous fire hazard, and even if no fire occurs, the unpleasant odor of the oil may make the building almost uninhabitable.

It is the object of my invention to eliminate the possibility of these dangerous and unpleasant occurrences, by providing an'oil supply system which includes a valve in the supply line desirably at or near the point at which the supply line is connected to the storage tank; which valve will be normally closed, but will be opened simultaneously with the normal operation of the pump. It is a further object of my invention to produce such a valve which will be opened as a result of the normal operation of the pump, and conveniently by the suction produced by the pump. It is a further object of my invention to provide a system of this sort in which the valve seat and valve stopper are located within the storage tank, so that the valve will prevent leakage of oil from the tank even though the connection between the storage tank and the supply line is completely broken.

In accomplishing the objects of my invention, I provide a fitting adapted to be connected directly to the storage tank and having a tubular portion extending within the storage tank; and I provide a valve seat and a valve stopper at the end of this tubular member. The tubular portion desirably extends to a point above the bottom of the tank, so that its opening will be above.

any collection of sludge or sediment in the bottom of the tank, to prevent any fouling of the valve at the end of the tubular member by any sediment and to prevent such sediment from getting into the supply line and pump. The valve stopper is operatively connected through the tubular member to control mechanism situated outside the storage tank, and the connection is deslrably so arranged that the valve will remain tightly closed even though the actuating mechanism is bent or broken. The actuating mechanism for this valve is all contained in the fitting of which the tubular member is a part and may be a pressure responsive device responsive to the oil pressure within the fitting. The oil supply line communicates with the storage tank through the fitting, so that the oil pressure Within the fitting is controlled by the operation of the pump in pulling oil through the oil supply line. The valve is desirably biased toward closed position by any head of oil in the oil tank; but is also mechanically urged toward closed position. It may be mechanically urged toward the closed position only by the inherent elasticity of the pressure responsive means, or it may also be so urged by one or more springs.

The accompanying drawing illustrates my invention: Fig. 1 is a diagrammatic view of an oilsupply system; Fig. 2 is a vertical section through a valve for use in such a system; Fig. 3 is a diagrammatic View of a modification of such oil supply systern; Fig. 4 is a vertical section of a springloaded valve embodying my invention, associated with a fitting for adapting such valve for use in another modification of the oil supply system; Fig. 5 is a diagrammatic showing of this other modification; and Fig. 6 is a vertical section of a modification of a valve embodying my invention.

The oil supply system shown diagrammatically in Fig. 1 is one in which the oil supply line 11 leading from the storage tank 10 is substantially horizontal throughout its entire length, so that there is no substantial oil head between the withdrawal opening in the storage tank and the delivery end of the supply line 11. In the system shown in Fig. l the oil flows from the storage tank 10 through a fitting 12 to the oil supply line 11 which delivers it to the pump 13, whence it is delivered under pressure'to the oil burner within the furnace 14.

, The fitting 12, which in accordance with my invention contains a valve, is shown in section in Fig. 2. The fitting is adapted to be screwed into an opening in the storage tank 10, and is provided with a tubular member 20 extending within the storage tank 10 to above any collection of sludge or sediment. At the inner end of the tubular member there is a valve stopper 21 which seats against the end of the tubular member 20. For operating the valve stopper 21, an operating rod 22 integral with the stopper 21 extends from such stopper axially through the tubular member 20 to outside the storage tank. Desirably, the operating rod 22 is positioned concentrically with the tubular member as by means of fins 23 which slidably engage the inner surface of the tubular member 20. Outside the storage tank, the fitting 12 is provided with an opening at which may be connected the supply line 11. Beyond this opening, the fitting 12 is enlarged to form a space for containing the pressure responsive means; and the operating rod 22 extends down into that space for connection to the pressure responsive means.

Desirably, the fins 23 are of considerable length axially of the tubular member 20 and are of considerable rigidity, in order that they will maintain the valve stopper in proper sealing relationship with its seat, even though the operating rod 22 is bent or broken. Also, the valve desirably closes in the direction of flow of oil therethrough, so any head of oil in the tank will tend to close the valve.

As shown, the pressure responsive means is a diaphragm bellows 25 mounted within the fitting by means of a sleeve 26 conveniently threaded into a central opening in the bottom of the fitting. The interior of the diaphragm bellows 25 is open to atmospheric pressure through this sleeve. The operating rod 22 extends through a central open- 1: ing in the upper diaphragm of the bellows, and is provided with a collar 27 and a nut 28 which engage the diaphragm on opposite sides to clamp it to the rod 22 and seal the opening through which the rod extends. The rod, being thus operatively connected to the diaphragm bellows, is normally held in closed position by the inherent bias of the bellows toward collapsed position, and is opened when reduced pressure within the fitting causes the bellows to expand.

While the inherent elasticity of the bellows is suflicient to maintain the valve in closed position, when that valve is used in the system shown in Fig. 1, it is desirable to provide some additional means for closing the valve when the valve is used in a system such as one of those shown in Figs. 3 and 5, where the withdrawal opening in the tank is substantially higher than the delivery end of the supply line 11 and in consequence there is a substantial oil head in the supply line tending toreduce the pressure at the end of the supply line which is connected to the fitting 12. I have shown in 4 a valve with such an additional means for maintaining the valve in closed position. As shown, this additional means for maintaining the valve in closed position comprises a spiral compression spring 30 surrounding the operating rod 22 and acting between a part of the fitting 12 and the end face of the diaphragm bellows 25 in a position to urge the bellows toward collapsed position.

Because in manufacturing such a valve as this it is impossible to anticipate the strength required in the spring 30, I desirably provide an adjusting means for adjusting the strength exerted by this spring 30. Conveniently, I accomplish this by providing a spider 31 at the end of the fitting l2, and providing this spider 31 with a central opening which overlies the nut 28 at the end of the operating rod 22. The interior of this central opening is screw-threaded, and within it is mounted a cup 32 which encloses a coil spring 33 acting between the bottom of the cup 32 and the end of the nut 28. The outer surface of the cup 32 is provided over a substantial portion of its axial extent with screw threads for co-operating with the screw threads of the spider 31, by means 10f which the cup 32 may be adjusted inwardly and outwardly to increase or decrease the pressure exerted by the coil spring 33 within the cup on the end of the nut 28. By this arrangement, the force exerted by the spring 30 is opposed by that exerted by the spring 33, and by reason of the adjustment provided for the spring 33, the spring 30 may be made to exert more or less pressure against the face of the bellows tending to collapse the bellows and close the valve.

In the arrangement shown in Fig. 3, the springloaded valve is mounted in the storage tank 10 in substantially the same manner as the valve shown in Fig. 1. That is, the valve is mounted in the bottom of the tank with its tubular portion 20 projecting above the bottom of the tank, and above any accumulation of sediment on such bottom.

When the storage tank 10 is buried in the ground outside the building containing the oil burning furnace 14 instead of being located in side such building as is shown in Figs. 1 and 3, it is customary to withdraw the oil from the storage tank by means of a pipe 35 extending through the top of the tank to near its bottom. When this system, shown in Fig. 5, is used, it is impractical to mount my valve directly on the tank, but instead the valve must be mounted in the supply line 11. Of course, the valve should be mounted near the tank in order that it may protect as much of the supply line as possible from any leaks.

In Fig. 4, I have shown associated with the spring-loaded valve a nipple 36 by which my I valve can be inserted in the supply line 11 without any structural changes. This nipple 36 comprises a cylindrical portion of substantially greater diameter than the tubular portion 20 of the valve fitting 12. Each end of the nipple 36 is provided with a reduced portion which forms a collar 37, and these collars 37 are internally screw-threaded for the reception of the fitting 12 at one end and a pipe forming part of the supply line 11 at the other end. The nipple 36 is of substantially greater length than the tubular portion 20 of the valve fitting 12 in order to provide ample space for the operation of the valve and the flow of oil through the valve.

It may be desirable instead of using the valve shown in Fig. 4 and the nipple 36 in the supply line 11 of a system such as that shown in Fig. 5, to provide a special fitting for this situation. Such a special fitting may take the form shown in Fig. 6. In this special form, the actuating mechanism for the valve and the casing for that actuating mechanism is identical with that of the valve shown in Fig. 4 and already described with reference to that valve. In this special fitting, instead of the tubular portion 20 as shown in Figs. 2 and 4, the end of the fitting is shaped in the form of an L 40. The valve stopper at the end of the operating rod 22 co-operates with a seat 41 at one extremity of L 40, and the other extremity of the L is provided internally with screw threads for the reception of a pipe. In this special form, the valve may be held concentric with its seat by means of fingers 42 projecting downwardly from the valve stopper and engaging the walls of the fitting just below the valve seat 41.

The operation of any one of the oil supply sys-- tems shown is substantially the same. When the pump is at rest, the valve will be closed and will be held closed by the inherent bias of the bellows 25 toward collapsed position and/or by the action of the spring 30. When the pump 13 starts to operate, either under manual control or under automatic temperature-responsive control, it will pump oil from the supply line 11 and reducethe pressure Within the valve fitting 12, and the reduced pressure will cause the bellows 25 to expand and to raise the valve stopper away from its seat. The fiow of oil past the valve stopper may then so increase the pressure within the fitting that the bellows will partially collapse, but I have found that the bellows will adjust itself to hold the valve stopper away from its seat sufficiently far to permit the oil-demand of the pump to be adequately supplied. When the pump stops, the pressure on the bellows 25 will be increased, and the bellows will collapse and close the valve. With the valve in closed position, the oil will be prevented from leaking either through the pump or through any break in the supply line. Indeed, the supply line might be completely broken away from the valve fitting without disturbing the valve.

I claim as my invention:

1. A. valve for use in a fluid supply system in which a pump draws fiuid through a supply line from a storage tank, comprising a fitting adapted to be secured in the bottom of the storage tank, a tubular member on said fitting for projecting to above the bottom of the storage tank, a valve stopper arranged to close the end of said tubular member, means for connecting the supply line in communication with the interior of said fitting, said valve stopper being yieldingly urged toward closed position, and pressure responsive means within said fitting arranged to move said stopper to open position in response to reduced pressure within said fitting.

2. A valve for use in a fiuid supply system in which a pump draws fluid through a supply line from a storage tank, comprising a fitting adapted to be secured in the storage tank, a tubular member on said fitting for projecting to above the bottom of the storage tank, a valve stopper arranged to close the end of said tubular member, spring means within said fitting arranged to yieldingly force said valve stopper toward closed position, means for connecting said supply line in communication with said fitting, pressure responsive means arranged to move said valve stopper toward open position in response to reduced pressure Within said fitting, and means accessible outside said fitting for adjusting the force exerted by said spring means.

3. A valve for use in a fiuid supply system in which a pump draws fiuid through a supply line from a storage tank, comprising a fitting adapted to be secured in the storage tank, a tubular member on said fitting for projecting to above the bottom of the storage tank, a valve stopper arranged to close the end of said tubular member, spring means within said fitting arranged to yieldingly force said valve stopper toward closed position, means for connecting said supply line in communication with said fitting, pressure responsive means arranged to move said valve stopper toward open position in response to reduced pressure within said fitting, a second spring means outside said casing adapted to oppose the force exerted by said first spring means, and an adjusting device for said second spring means.

4. In an oil supply system for a furnace, a tank, a tubular valve casing projecting through the wall of said tank, a valve seat at the inner end of said casing, a valve stopper associated with said seat and arranged to close in the direction of fluid flow through said casing, a stem on said stopper extending through said casing, a cylindrical enlargement at the outer end of said casing and provided with a cap, a bellows secured at one end at the edges of a central opening in said cap, said stem extending through a fitted opening in the other end of said bellows, a collar on said stem in position to have the edges of said fitted opening clamped against it, and a nut on the end of said stem for so clamping said edges, said nut being accessible through said central opening.

5. The invention defined in claim 4 with the addition of means within said casing for biasing said valve to closed position, and means acting on said nut for regulating the effect of said biasing means.

6. A valve adapted for use in a furnace oil supply system, comprising a tubular casing, a valve seat at one end thereof, a valve stopper associated with said seat and arranged to close in the direction of fluid fiow through said casing, a stem on said stopper extending through said casing, a cylindrical enlargement at the other end of said casing and provided with a cap, a bellows secured at one end at the edges of a central opening in said cap, said stem extending through a fitted opening in the other end of said bellows, a collar on said stem in position to have the edges of said fitted opening clamped against it, and a nut on the end of said stem for so clamping said edges, said nut being accessible through said central opening.

'7. The invention defined in claim 6 with the addition of means within said casing for biasing said valve to closed position, and means acting on said nut for regulating the effect of said biasing means.

JOHN N. HARDY. 

